The following descriptions are exemplary embodiments only, and are not intended to limit the scope, applicability or configuration of the invention in any way. Rather, the following description provides a convenient illustration for implementing exemplary embodiments of the invention. Various changes to the described embodiments may be made in the function and arrangement of the elements described without departing from the scope of the invention as set forth in the appended claims.
As shown in
The gear assembly mainly contains a chain wheel 210 sandwiched between a first plate 100 and a second plate 110. The second plate 110 has a number of parallel supporting rods 111 around the chain wheel 210 running perpendicularly through the first plate 100. Around the circumference of the chain wheel 210, a number of indentations 211 conforming to the shape of a chain 400's links are provided. Therefore, when the chain wheel 210 turns, the chain 400 surrounding the chain wheel 210 is pulled accordingly. A first supporting rod 111 runs through a shackle 600 also sandwiched between the first and second plates 100 and 110 for hanging the hoist device. To properly align and drive the chain 400, two fan-shaped chain guiding blocks 260 are provided on two opposing second and third supporting rods 111, respectively, together with an elongated chain stopping block 270 provided on a fourth supporting rod 111, all interfacing with the chain wheel 210 at the circumference. The chain guiding and stopping blocks 260 and 270 are also located between the first and second plates 100 and 110.
The chain wheel 210 has a tubular end (not numbered) that penetrates through the first plate 100 into the center of a main gear 250 located outside the first plate 100. The main gear 250 is engaged by a pair of passive gears 240, which in turn are engaged by a driving gear 201 at a first end of a main axle 200. The main axle 200 rotatably runs through the main gear 250 and the chain wheel 210, and extends outside the second plate 110 for an appropriate distance.
The ratchet braking assembly is at the outside of the second plate 110. Starting from the second plate 100 outward, there are a base disc 300, a first brake ring 310, a ratchet wheel 320, a second brake ring 310, and a cap disc 220. Two opposing stopping blocks 330 engage the teeth of the ratchet wheel 320 so that the ratchet wheel can only turn in one direction. Together with the friction of the brake rings 310, the ratchet braking assembly prevents a lifted object from falling or slipping. The stopping blocks 330 are mounted on two sticks 112 extended perpendicularly from the outside of the second plate 110, respectively.
The main axle 200 penetrates through the foregoing ratchet braking assembly and, at a second end of the main axle 200, there are threads and grooves (not numbered) for interfacing with the cap disc 220 and for fastening to a nut 500. A hexagonal cylinder 221 is provided on the outside of the cap disc 220, which plugs into a first end of a hexagonal cylindrical sleeve 230. A second end of the sleeve 230 also provides an axial rectangular socket 231. An ordinary hexagonal wrench or a power tool 700 (using air or electricity) having an appropriate plug can be used to drive the sleeve 230 and, thereby, the main axle 200 to turn. As described above, the chain wheel 210 will be turned as well so as to pull the chain 400. In the man time, as the main axle 200 turns, the cap disc 220 closes in to press the ratchet wheel 320 and the brake rings 310 against the base disc 300. The friction therebetween will cause the ratchet wheel 320 to turn as well. When the driving to the main axle 200 stops, the friction exerted by the brake rings 310 and the effect of the stopping blocks 330 hold the lifted object at its place. To lower the object, by using the wrench or power tool to turn the main axle 200 in the opposite direction, the cap disc 220 is moved away from the ratchet wheel 320 and the brake rings 310. As such, the friction and the stopping blocks 330 of the ratchet wheel 320 will not prevent the chain wheel 210 to turn in the opposite direction to lower the object.
It will be understood that each of the elements described above, or two or more together may also find a useful application in other types of methods differing from the type described above.
While certain novel features of this invention have been shown and described and are pointed out in the annexed claim, it is not intended to be limited to the details above, since it will be understood that various omissions, modifications, substitutions and changes in the forms and details of the device illustrated and in its operation can be made by those skilled in the art without departing in any way from the spirit of the present invention.
Number | Date | Country | Kind |
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095207962 | Oct 2006 | TW | national |